Mixing device.



N0. 855,631. PATENTED JUNE 4, 1907.

J. G. W. GRETH. I MIXING DEVICE.

APPLIOATION FILED OCT. 2. 1906.

THE NORRIS Psnms cu.,'w.4snma1ou, o, c.

nnrrni) STATESWPATNT enrich.

JOHN G. W. GRETII, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO WM. B;

SOAIFE & SONS COMPANY, OF PITTSBURG, PENNSYLVANIA, A CORPORA- TION OF NEW JERSEY.

MIXING DEVICE.

To all whmn it may concern.-

Be it known that I, JOHN C. W. GRETH, a citizen of the United States, residing at Pittsburg, in the State of Pennsylvania, have in vented certain new and useful Improvements in Mixing Devices, of which the following is a specification.

My invention relates to apparatus for making up and mixing liquids such as the chemical solutions used in water purifying apparatus, and its primary object is to afford 'means for uniformly mixing and dissolving a.

chemical and to break up lumps, etc. in the chemical. It is particularly designed for use in preparing the lime or soda or other solutions in water purifying apparatus such as described in my prior patents.

In the accompanying drawings Figure l is a vertical central section of the mixing vessel and parts of the stirring device. Fig. 2 is a section of the same vessel at right angles to the section of Fig. l, and Fig. 3 is a-plan view of the stirring paddles and section of the tank on line (3) inFig. 2.

Ordinarily in mixing such a solution for example as milk of lime for the purposes above noted, it is customary to dump into a tank a lot of lime in the solid state and then pour in water and stir the mixture up. The stirring results in accumulating the large lumps in the main part of the material near the center of the revolving mass of liquid and frequently lumps pass out with the supposedly dissolved solution. In order to prevent these defects I have provided in a tank 4 a vertical shaft 5 which may be driven by a crank shaft 6 or any other convenient means, and the bottom of the shaft 5 has.

keyed to it a casting 7 for carrying the paddles. This casting is of a general conical shape as shown and rests directly over a bottom plate 8 fixed in the tank and having a socket for a bearing of the shaft 5. The bottom of the casting 7 is a plate 9 which is slightly conical as shown and cooperating with the bottom plate 8 forms a grinder in order to reduce any lumps that may occur. The solution passes out through openings 10 in the bottom plate 8 and thence into a delivery pipe 11 through which it is drawn by a pump or ejector 12 for delivery to the re-action tank. On the casting 7 are provided a series of inclined seats upon which are car- Specification of Letters Patent.

Patented June 4, 1907.

Application filed October 2,1906. Serial No. 337,059.

ried paddles 13 and these paddles are set at an angle as shown and arranged opposite each other so that upon revolving the shaft 5 the paddles will throw the liquid constantly upward and outward thereby driving the lime or other material toward the outer side of the tank and away from the center where it tends to accumulate. The paddle being set at its angle also causes vertical currents in the liquid and results in a thorough mixing. At the same time if any lumps are found in the liquid they are met by the grinding surfaces 8, 9, when they attempt to reach the outlet and are centrifugally thrown outward or ground into a fine powder vbefore they may escape. The whole device there fore results in a thorough mixing of the solid and liquid and assurance against the passing out of any lumps or solid matter, at the same time preventing any accumulation of solid matter at the center of the tank.

The various advantages of the device will readily occur to those familiar with the art.

Having thus described my invention and illustrated its use, what I claim as new and desire to patent, is the following:

1. A mixing device comprising a tank having an outlet opening in its bottom, a series of paddles placed above and covering said opening and means to revolve the paddles, said paddles being inclined so as to throw the fluidboth upwardly and outwardly.

2. The combination with a mixing tank and revolving paddles therein, of an outlet and means to grind lumps of material entering the outlet, substantially as described.

3. In a mixer the combination with a tank and bottom plate having outlet openings, of a revolving plate set over and close to the bottom plate to provide a grinder, paddles mounted at an angle to the horizontal and means for revolving them above said openmgs.

4. In a mixing device the combination with a vertical shaft having paddles thereon set with their blades at an angle to the horizontal, means to revolve the said shaft, an outlet beneath the paddles and a grinding device inclosing the outlet.

5. A mixing device comprising a tank and a plate in the bottom of the tank having outlets, a second plate set above and covering the outlet and means to revolve it whereby to form a grinding mill with the first plate, substantially as described.

6. The combination with a tank having a metallic bottom plate with outlet openings at its center, a slightly conical plate set above said outlet openings, and means to revolve the said plate, whereby lumps of material attempting to escape are ground up, substantially as described.

7. The combination with a tank having a series of revolving paddles arranged to cause vertical currents in the tank, and a grinding device under the paddles to reduce lumps which may settle on the bottom of the tank, substantially as set forth.

In testimony whereof I have hereunder signed my name in the presence of the two subscribed Witnesses.

JOHN C. W. GRETH.

In presence of F. W. H. CLAY, CHAs. S. LEPLEY. 

